The present invention relates to an optical beam shaping system, and more particularly to an optical beam shaping system for use in an optical signal pickup device for radiating a laser beam spot onto an optical information storage disk to record signals on and reproduce signals from the optical information storage disk.
Conventional optical beam shaping systems employed in optical signal pickup devices have proven unsatisfactory in that they lower the light utilization efficiency which is the ratio of the power of the beam emitted from the objective lens to the power of the beam emitted from the semiconductor laser in the optical signal pickup devices. The semiconductor laser has therefore been required to produce a high laser output, and has been costly to manufacture.